bdrv_append() is called with bs_top AioContext held, but
bdrv_attach_child_noperm() could change the AioContext of bs_top.
bdrv_replace_node_noperm() calls bdrv_drained_begin() starting from
commit 2398747128 ("block: Don't poll in bdrv_replace_child_noperm()").
bdrv_drained_begin() can call BDRV_POLL_WHILE that assumes the new lock
is taken, so let's temporarily hold the new AioContext to prevent QEMU
from failing in BDRV_POLL_WHILE when it tries to release the wrong
AioContext.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2168209
Reported-by: Aihua Liang <aliang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230214171621.11574-1-sgarzare@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates CURLOPT_PROTOCOLS and CURLOPT_REDIR_PROTOCOLS in
favour of *_STR variants, specifying the desired protocols via a
string.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1440
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230123201431.23118-1-anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-14-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_co_create_opts_simple() runs in a coroutine. Therefore it is not
allowed to open images directly. Fix the call to use the corresponding
no_co_wrapper instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-13-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-12-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-11-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-10-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-9-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-8-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine, as does
qcow2_do_open(). Therefore they are not allowed to open images directly.
Fix the calls to use the corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-6-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-5-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
.bdrv_co_create implementations run in a coroutine. Therefore they are
not allowed to open images directly. Fix the calls to use the
corresponding no_co_wrappers instead.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-4-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Images can't be opened in coroutine context because opening needs to
change the block graph. Add no_co_wrappers so that coroutines have a
simple way of opening images in a BH instead.
At the same time, mark the wrapped functions as no_coroutine_fn.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-3-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Some functions must not be called from coroutine context. The common
pattern to use them anyway from a coroutine is running them in a BH and
letting the calling coroutine yield to be woken up when the BH is
completed.
Instead of manually writing such wrappers, add support for generating
them to block-coroutine-wrapper.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230126172432.436111-2-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failures (just print, no abort).
There are several paths in curl_open() that can lead to the out_noclean
label without s->sockets being allocated, so clean it only if it has
been allocated.
Example reproducer:
$ qemu-img info -f http ''
qemu-img: GLib: g_hash_table_foreach_remove: assertion 'hash_table != NULL' failed
qemu-img: GLib: g_hash_table_destroy: assertion 'hash_table != NULL' failed
qemu-img: Could not open '': http curl driver cannot handle the URL '' (does not start with 'http://')
Closes: https://gitlab.com/qemu-project/qemu/-/issues/1475
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230206132949.92917-1-hreitz@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This enables clang's thread safety analysis (TSA), which we'll use to
statically check the block graph locking.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-9-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230117135203.3049709-4-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
FreeBSD implements pthread headers using TSA (thread safety analysis)
annotations, therefore when an application is compiled with
-Wthread-safety there are some locking/annotation requirements that the
user of the pthread API has to follow.
This will also be the case in QEMU, since bsd-user/mmap.c uses the
pthread API. Therefore when building it with -Wthread-safety the
compiler will throw warnings because the functions are not properly
annotated. We need TSA to be enabled because it ensures that the
critical sections of an annotated variable are properly locked.
In order to make the compiler happy and avoid adding all the necessary
macros to all callers (lock functions should use TSA_ACQUIRE, while
unlock TSA_RELEASE, and this applies to all users of pthread_mutex_lock
and pthread_mutex_unlock), simply use TSA_NO_TSA to supppress such
warnings.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230117135203.3049709-3-eesposit@redhat.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
FreeBSD implements pthread headers using TSA (thread safety analysis)
annotations, therefore when an application is compiled with
-Wthread-safety there are some locking/annotation requirements that the
user of the pthread API has to follow.
This will also be the case in QEMU, since util/qemu-thread-posix.c uses
the pthread API. Therefore when building it with -Wthread-safety, the
compiler will throw warnings because the functions are not properly
annotated. We need TSA to be enabled because it ensures that the
critical sections of an annotated variable are properly locked.
In order to make the compiler happy and avoid adding all the necessary
macros to all callers (lock functions should use TSA_ACQUIRE, while
unlock TSA_RELEASE, and this applies to all users of pthread_mutex_lock
and pthread_mutex_unlock), simply use TSA_NO_TSA to supppress such
warnings.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230117135203.3049709-2-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Make use of pthread_set_name_np() to be able to set the threads name
on OpenBSD.
Signed-off-by: Brad Smith <brad@comstyle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <Y57NrCmPTVSXLWC4@humpty.home.comstyle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VHOST_BACKEND_F_IOTLB_ASID is the feature bit, not the bitmask. Since
the device under test also provided VHOST_BACKEND_F_IOTLB_MSG_V2 and
VHOST_BACKEND_F_IOTLB_BATCH, this went unnoticed.
Fixes: c1a1008685 ("vdpa: always start CVQ in SVQ mode if possible")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
In stream mode, if the server shuts down there is currently
no way to reconnect the client to a new server without removing
the NIC device and the netdev backend (or to reboot).
This patch introduces a reconnect option that specifies a delay
to try to reconnect with the same parameters.
Add a new test in qtest to test the reconnect option and the
connect/disconnect events.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
When the VM is stopped using the HMP command "stop", soon the handler will
stop reading from the vmnet interface. This causes a flood of
`VMNET_INTERFACE_PACKETS_AVAILABLE` events to arrive and puts the host CPU
at 100%. We fix this by removing the event handler from vmnet when the VM
is no longer in a running state and restore it when we return to a running
state.
Signed-off-by: Joelle van Dyne <j@getutm.app>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Increase the allocated buffer size to fit larger packets.
Given that jumboframes can commonly be up to 9000 bytes the closest suitable
value seems to be 16 KiB.
Tested by running qemu towards a Linux L2TPv3 endpoint and pushing
jumboframe traffic through the interfaces.
Signed-off-by: Christian Svensson <blue@cmd.nu>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Currently, VMXNET3_MAX_MTU itself (being 9000) is not considered a
valid value for the MTU, but a guest running ESXi 7.0 might try to
set it and fail the assert [0].
In the Linux kernel, dev->max_mtu itself is a valid value for the MTU
and for the vmxnet3 driver it's 9000, so a guest running Linux will
also fail the assert when trying to set an MTU of 9000.
VMXNET3_MAX_MTU and s->mtu don't seem to be used in relation to buffer
allocations/accesses, so allowing the upper limit itself as a value
should be fine.
[0]: https://forum.proxmox.com/threads/114011/
Fixes: d05dcd94ae ("net: vmxnet3: validate configuration values during activate (CVE-2021-20203)")
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This patch replaces hw_error to guest error log for [read|write]b
accesses when mode_16bit is enabled. This avoids aborting qemu.
Fixes: 1248f8d4cb ("hw/lan9118: Add basic 16-bit mode support.")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1433
Reported-by: Qiang Liu <cyruscyliu@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Qiang Liu <cyruscyliu@gmail.com>
Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Just because a NIC model is compiled into the QEMU binary does not
necessary mean that it can be used with each and every machine.
So let's rather talk about "available" models instead of "supported"
models, just to avoid confusion.
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Running QEMU with "-nic help" used to work in QEMU 5.2 and earlier versions
(it showed the available netdev backends), but this feature got broken during
some refactoring in version 6.0. Let's restore the old behavior, and while
we're at it, let's also print the available NIC models here now since this
option can be used to configure both, netdev backend and model in one go.
Fixes: ad6f932fe8 ("net: do not exit on "netdev_add help" monitor command")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The code that collects the available NIC models is not really specific
to PCI anymore and will be required in the next patch, too, so let's
move this into a new separate function in net.c instead.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Fork-fuzzing provides a few pros, but our implementation prevents us
from using fuzzers other than libFuzzer, and may be causing issues such
as coverage-failure builds on OSS-Fuzz. It is not a great long-term
solution as it depends on internal implementation details of libFuzzer
(which is no longer in active development). Remove it in favor of other
methods of resetting state between inputs.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
As we have repplaced fork-based fuzzing, with reboots - we can no longer
use a timeout+exit() to avoid slow inputs. Libfuzzer has its own timer
that it uses to catch slow inputs, however these timeouts are usually
seconds-minutes long: more than enough to bog-down the fuzzing process.
However, I found that slow inputs often attempt to fill overly large DMA
requests. Thus, we can mitigate most timeouts by setting a cap on the
total number of DMA bytes written by an input.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
As we are converting most fuzzers to rely on reboots to reset state,
introduce an API to make sure reboots are invoked in a consistent
manner.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
We use sparse-mem for fuzzing. For long-running fuzzing processes, we
eventually end up with many allocated sparse-mem pages. To avoid this,
clear the allocated pages on system-reset.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
To show my interest in the VFIO susbsystem, let's start reviewing code.
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230119185736.616664-1-clg@kaod.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that VFIO migration protocol v2 has been implemented and v1 protocol
has been removed, update the documentation according to v2 protocol.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-12-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Sort the migration section of VFIO trace events file alphabetically
and move two misplaced traces to common.c section.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-11-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that v2 protocol implementation has been added, remove the
deprecated v1 implementation.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-10-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Implement the basic mandatory part of VFIO migration protocol v2.
This includes all functionality that is necessary to support
VFIO_MIGRATION_STOP_COPY part of the v2 protocol.
The two protocols, v1 and v2, will co-exist and in the following patches
v1 protocol code will be removed.
There are several main differences between v1 and v2 protocols:
- VFIO device state is now represented as a finite state machine instead
of a bitmap.
- Migration interface with kernel is now done using VFIO_DEVICE_FEATURE
ioctl and normal read() and write() instead of the migration region.
- Pre-copy is made optional in v2 protocol. Support for pre-copy will be
added later on.
Detailed information about VFIO migration protocol v2 and its difference
compared to v1 protocol can be found here [1].
[1]
https://lore.kernel.org/all/20220224142024.147653-10-yishaih@nvidia.com/
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>.
Link: https://lore.kernel.org/r/20230216143630.25610-9-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
To avoid name collisions, rename functions and structs related to VFIO
migration protocol v1. This will allow the two protocols to co-exist
when v2 protocol is added, until v1 is removed. No functional changes
intended.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-8-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move vfio_dev_get_region_info() logic from vfio_migration_probe() to
vfio_migration_init(). This logic is specific to v1 protocol and moving
it will make it easier to add the v2 protocol implementation later.
No functional changes intended.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-7-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently VFIO migration doesn't implement some kind of intermediate
quiescent state in which P2P DMAs are quiesced before stopping or
running the device. This can cause problems in multi-device migration
where the devices are doing P2P DMAs, since the devices are not stopped
together at the same time.
Until such support is added, block migration of multiple devices.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-6-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_devices_all_running_and_saving() is used to check if migration is
in pre-copy phase. This is done by checking if migration is in setup or
active states and if all VFIO devices are in pre-copy state, i.e.
_SAVING | _RUNNING.
In VFIO migration protocol v2 pre-copy support is made optional. Hence,
a matching v2 protocol pre-copy state can't be used here.
As preparation for adding v2 protocol, change
vfio_devices_all_running_and_saving() logic such that it doesn't use the
VFIO pre-copy state.
The new equivalent logic checks if migration is in active state and if
all VFIO devices are in running state [1]. No functional changes
intended.
[1] Note that checking if migration is in setup or active states and if
all VFIO devices are in running state doesn't guarantee that we are in
pre-copy phase, thus we check if migration is only in active state.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-5-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently, if IOMMU of a VFIO container doesn't support dirty page
tracking, migration is blocked. This is because a DMA-able VFIO device
can dirty RAM pages without updating QEMU about it, thus breaking the
migration.
However, this doesn't mean that migration can't be done at all.
In such case, allow migration and let QEMU VFIO code mark all pages
dirty.
This guarantees that all pages that might have gotten dirty are reported
back, and thus guarantees a valid migration even without VFIO IOMMU
dirty tracking support.
The motivation for this patch is the introduction of iommufd [1].
iommufd can directly implement the /dev/vfio/vfio container IOCTLs by
mapping them into its internal ops, allowing the usage of these IOCTLs
over iommufd. However, VFIO IOMMU dirty tracking is not supported by
this VFIO compatibility API.
This patch will allow migration by hosts that use the VFIO compatibility
API and prevent migration regressions caused by the lack of VFIO IOMMU
dirty tracking support.
[1]
https://lore.kernel.org/kvm/0-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com/
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-4-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
As part of its error flow, vfio_vmstate_change() accesses
MigrationState->to_dst_file without any checks. This can cause a NULL
pointer dereference if the error flow is taken and
MigrationState->to_dst_file is not set.
For example, this can happen if VM is started or stopped not during
migration and vfio_vmstate_change() error flow is taken, as
MigrationState->to_dst_file is not set at that time.
Fix it by checking that MigrationState->to_dst_file is set before using
it.
Fixes: 02a7e71b1e ("vfio: Add VM state change handler to know state of VM")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Link: https://lore.kernel.org/r/20230216143630.25610-3-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Stefano Garzarella
Anton Johansson
Kevin Wolf
Hanna Czenczek
Emanuele Giuseppe Esposito
Brad Smith
Eugenio Pérez
Laurent Vivier
Joelle van Dyne
Christian Svensson
Fiona Ebner
Qiang Liu
Thomas Huth
Alexander Bulekov
Cédric Le Goater
Avihai Horon